Right, I'm not claiming Glass was good, but it at least attempted to use the glasses form factor for something.
The camera to capture 'what you see' seems like using the form factor pretty well.
Mic and speakers, too.
Glass attempted a display, but IMHO, it was unusable, so I understand why you would try the same thing with no display. Or the same thing, but mounted on your wrist (Google Wear).
I don't know about everyone, but I found it pretty hard to use. Caveat, I didn't get them fit to me, I was supervising an intern working on a speculative Glass project, and they were fit to him.
AR would be neat, but voice interfaces are acheivable at an approachable cost. I'm not one to talk to a computer, and I wear prescription lenses, so these glasses don't appeal to me, but I can see there's a market there, not sure how big or if Meta can capture it.